A regular sized (24") DPW cover over a larger manhole, with the long inscription for the Valve and Hyde Co. on the expansive seating. The patent date on the rim (1925) whould point to the second age of the Department of Public Works from 1939 to 1975 for the cover. The Valve and Hyde Company is somewhat elusive - so keep an open eye!
The central monogram surrounded by 7 rings of stubs is a recurring design for many types of covers in the mid 20th C. Note that the seating rim still retains 3 stabilizing pegs even at this late date.
Undoubtably a sewer cover
The central cover is the standard cover issued by the NYC Department of Public Works and similar covers are found throughout the 5 boroughs. This one with the Valve and Hyde rim is on West Broadway and Lispenard St. in Manhattan